A few weeks ago, the Guardian ran a story by Oscar Schwartz about Affectiva, a company that plans to market “emotion-detection technology.” That phrase, taken out of context, is an effective piece of hype even if it's meant as a scary warning, as it concisely reinforces the company’s pitch: It suggests that emotions are discrete, universally identifiable things that actually can be detected, in individuals, in isolation, as if emotions did not occur interpersonally and did not depend on context.